Generally, semiconductor devices having a high integration degree and a rapid response speed are desirable. The technology of manufacturing the semiconductor devices has improved an integration degree, a reliability and/or a response speed of semiconductor devices. As the integration degree of the semiconductor devices increases, a design rule of the semiconductor devices may decrease.
The semiconductor devices generally may include conductive structures (e.g., wirings, plugs, conductive regions or electrodes) and insulation structures (e.g., dielectric layers, or insulating interlayers) that may electrically isolate the conductive structures. Forming such structures may employ a film deposition process. Examples of the film deposition process may include a physical vapor deposition (PVD) process, a chemical vapor deposition (CVD) process, or an atomic layer deposition (ALD) process.
The PVD process has an undesirable property in that it fills a hole, a gap or a trench, and thus generates a void in the hole, the gap or the trench. As the integration degree of the semiconductor device increases, a width of the hole may become narrow and an aspect ratio of the hole may be increased. When the width of the hole is small and the aspect ratio of the hole is large, a depositing material may be readily accumulated on an entrance of the hole to block the entrance of the hole prior to completely filling the inside of the hole and thus a void in the hole may be generated. The void may increase an electrical resistance of a conductive structure to deteriorate performance of the semiconductor device and to cause a defect of the semiconductor device. However, in the CVD process or the ALD process, filling the hole is superior when compared with the PVD process, and thus the CVD or PVD process may be employed in filling the hole, the gap or the trench in a semiconductor manufacturing process.
In the CVD process or the ALD process, a precursor is introduced into a chamber using a bubbling system or an injection system. For example, in the bubbling system, a precursor of a liquid state or a solid state is vaporized by bubbling the precursor with a carrier gas, and the vaporized precursor is introduced into the chamber with the carrier gas. That is, the precursor of the liquid state or the solid state is vaporized before introducing into the chamber to transform into the vapor state. As a result, the precursor is heated and a chamber maintains a high temperature during introduction of the precursor into the chamber. Thus, a high thermal stability may be required in the precursor used for forming the layer. When the precursor is unstable to heat and to be easily dissociated, it is difficult to control a process condition and to form a layer having a uniform thickness. Thus, electrical characteristics of the semiconductor devices may be deteriorated.